A comparison of different procedures for principal component analysis in the presence of outliers |
| |
Authors: | B Bari? Alkan Cemal Atakan Nesrin Alkan |
| |
Institution: | 1. Faculty of Science and Arts, Department of Statistics, Sinop University, 57000 Sinop, Turkey;2. Faculty of Science, Department of Statistics, Ankara University, 06100 Ankara, Turkey |
| |
Abstract: | Principal component analysis (PCA) is a popular technique that is useful for dimensionality reduction but it is affected by the presence of outliers. The outlier sensitivity of classical PCA (CPCA) has caused the development of new approaches. Effects of using estimates obtained by expectation–maximization – EM and multiple imputation – MI instead of outliers were examined on the artificial and a real data set. Furthermore, robust PCA based on minimum covariance determinant (MCD), PCA based on estimates obtained by EM instead of outliers and PCA based on estimates obtained by MI instead of outliers were compared with the results of CPCA. In this study, we tried to show the effects of using estimates obtained by MI and EM instead of outliers, depending on the ratio of outliers in data set. Finally, when the ratio of outliers exceeds 20%, we suggest the use of estimates obtained by MI and EM instead of outliers as an alternative approach. |
| |
Keywords: | principal component analysis missing value expectation–maximization multiple imputation outliers |
|
|